Starter dieing?

[CCiatteo]

Last night I jumped into my truck and noticed that the motor cranked real slow, but fired and once running ran fine. I chalked it up to sitting in the cold (high teens - low 20's) for 14 hours. But when I got home (30 minute drive down the highway) to the safety of my driveway I turned it off waited 10 minutes and went out to start it again. Same thing, noticeably slow cranking speed. I check the batteries (both new this past summer, red top optimas) and cables (all tight and and no corrosion, Boeshield works really well) so all I am left with is the starter. Today I take my other car to work and when I get home I check the battery cable at the starter, and the stud appears to be loose, not the cable, but the whole stud. This can't be good. And I see a sticker on the starter that says "World Class - Remanufactured" so now I am suspecting the started is an offshore rebuilt unit and is dieing.

I put Larry B's super contacts in when I first bought the truck about 3 years ago, could those contacts be worn?

Do I have my current starter rebuilt by a local shop, who I have dealt with in the past and had excellent results or do I just buck up and order a NEW Denso unit from Larry B?

Any other possible idea's before I plunk down $$$ for another starter.

Thanks
Chris